An investigation was launched Sunday and closed less than a day later after police said a Buena Park resident discovered a few human bones while digging in his backyard.

The remains were found outside a home in the 8200 block of Commonwealth Avenue. The discovery was made by the homeowner just before 6 p.m. Sunday.

After analyzing the bones, Orange County Coroner's Office investigators determined Monday they were of Native American descent and had likely been buried in the homeowner's backyard for a lengthy period of time.

The Orange County Sheriff's Department coroner's division combed the scene with a cadaver dog after the initial discovery. According to Buena Park police, the bones were found in a grave about 3-4 feet deep.

"The dog searched the entire lot and was not able to locate any other remains than what was discovered last night," said Buena Park Police Department Sgt. Mike Lovchik.

Authorities do not believe criminal activity was involved and the investigation has been closed.

Arrangements will be made with the Native American Heritage Commission to properly re-inter the remains, police said.